Events at Physics |
Events on Thursday, April 25th, 2013
- NPAC (Nuclear/Particle/Astro/Cosmo) Forum
- Search for Neutrino-less Double Beta Decay with EXO-200
- Time: 2:30 pm
- Place: 4274 Chamberlin
- Speaker: Delia Tosi, Stanford University
- Abstract: Neutrino-less double beta decay may answer essential open questions in neutrino physics. While double beta decay accompanied by the emission of two neutrinos is allowed by the standard model, the neutrino-less process requires neutrinos to be Majorana particles. Detecting this decay could determine the nature of neutrinos, the neutrino effective mass, and the mass hierarchy. The Enriched Xenon Observatory (EXO) is an experimental program searching for neutrino-less double beta decay in xenon-136. The first stage of this program, EXO-200, features 200 kg of liquid xenon. The detector, located at the Waste Isolation Pilot Plant in New Mexico, has been taking data for two years. EXO-200 detected for the first time two-neutrino double beta decay of xenon, the slowest process ever measured directly. Furthermore it set a strong limit on the rate of zero-neutrino double beta decay. I will describe EXO-200 as well as prospects for the future large-scale detector nEXO.
- Host: Halzen
- Astronomy Colloquium
- What did we learn about the Milky Way during the last decade, and what shall we learn using Gaia and LSST?
- Time: 3:45 pm
- Place: 4421 Sterling Hall
- Speaker: Zeljko Ivezic, University of Washington
- Abstract: Studies of stellar populations, understood to mean collections of stars with common spatial, kinematic, chemical, and/or age distributions, have been reinvigorated during the last decade by the advent of large-area sky surveys such as SDSS, 2MASS, RAVE, and others. These data, together with theoretical and modeling advances, are revolutionizing our understanding of the nature of the Milky Way, and galaxy formation and evolution in general. These recent<br>
developments have made it clear that the Milky Way is a complex and dynamic structure, one that is still being shaped by the merging of neighboring smaller galaxies. I will review the progress over the last decade, and will briefly discuss new breakthroughs expected from Gaia and LSST surveys, which will improve measurement precision manyfold, and comprise billions of individual stars.<br>
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- Host: Bob Benjamin